This code was popping up everywhere this method is called. Seems bad to
duplicate it. Really what the caller wants to know is 'is the request
valid or a potential CSRF exploit?'. This gets the API closer to that.
Some other misc cleanup
- docs for IAntiforgeryTokenGenerator
- Add HttpContext parameter where to all IAntiforgeryGenerator methods
- rename parameters on DefaultAntiforgery
Ryan Nowak
Doug Bunting
N. Taylor Mullen